1. Field of the Invention
The present invention relates to a vehicle stop control system that automatically stops an internal combustion engine when predetermined stop conditions are satisfied, and then automatically restarts the engine when predetermined restart conditions are satisfied.
2. Description of the Related Art
A conventional vehicle stop control system of this type is disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 2011-202638. This stop control system executes idling stop during traveling in which an internal combustion engine is stopped without waiting for a vehicle to stop during decelerating traveling of the vehicle when predetermined stop conditions are satisfied. Further, it is determined whether or not a state in which a vehicle speed is not lower than a predetermined speed (e.g. 40 km/h) continues for a predetermined time period (e.g. 10 seconds) or longer. If it is determined that the above-mentioned condition concerning the vehicle speed is not satisfied, it is judged that the vehicle is traveling on e.g. a back street or a country road, on which the vehicle has to repeatedly perform a temporary stop, or the vehicle is traveling in a traffic jam, so that idling stop is inhibited. This prevents troublesomeness and discomfort from being caused by frequent execution of idling stop and restart.
In the above-described conventional vehicle stop control system, as a condition for executing idling stop, there is roughly defined a condition that the state in which the vehicle speed is not lower than the predetermined speed continues for the predetermined time period or longer, and unless this condition is satisfied, idling stop is inhibited. Therefore, for example, if a low-speed traveling state in which the vehicle speed does not reach the predetermined speed continues for a long time, idling stop is not executed at all, resulting in restriction of idling stop more than necessary, which makes it impossible to sufficiently obtaining the effect of improvement in fuel economy by idling stop.